The present invention relates in general to sheet folding devices, and in particular to a new and useful folding machine which includes a protective housing :for containing a plurality of rollers and a pair of pockets which are used in conjunction with each other to twice fold a piece of sheet material such as paper.
Folders of this kind are known (German patents 3,025,239 and 3,027,344). Hood-like multipart housings are provided as protection, especially for feeders that handle large size sheets, to cover the upper parts of the machine and enclose the lower part thereof by a tray-like structure. Hood and pocket shaped envelopes made of sound absorbing or deadening materials, such as hard foam, are also employed with smaller folders,as a protection against noise produced by the machine. Such envelopes are usually either slipped over the folding pockets, or put over the middle part of the machine.
The manufacture of such multipart noise absorbing guards is expensive and in addition, the parts must individually be removed from the machine if the sheet stops are to be adjusted, and then put in place again, which not only is time consuming but also involves the risk of damaging the parts. The same inconvenience is encountered in instances of failure in operation, such as a paper jam.